High versus Low-Intensity Resistance Training on Bone Mineral Density and Content Acquisition by Postmenopausal Women with Osteopenia: A Randomized Controlled Trial

Background: The menopause stage in women reduces estrogen levels and bone indicators. This study compared the effects of high-intensity resistance training (HIRT) and low-intensity resistance training (LIRT) on bone mineral density (BMD) and bone mineral content (BMC), T-score, and Z-score in postmenopausal women with osteopenia. Methods: A randomized controlled trial was conducted among 45 postmenopausal women, aged 50 to 60, who were randomly assigned into 3 parallel groups (n = 15 in each). The exercise program was performed by the interventional groups—the HIRT and LIRT groups—at 4 different intensities, 3 times a week for 24 weeks: 8 repetitions at 80% of 1 repetition maximum and 16 repetitions at 40% of 1 repetition maximum. The evaluated areas (BMD, BMC, T-score, and Z-score) included the lumbar spine (LS) and the femur neck (FN) using a DEXA machine. One-way analysis of covariance and Bonferroni's post hoc tests were used for data analysis. Results: The results indicated significant differences in BMD, BMC, T-scores, and Z-scores between the means of the LS and the FN in all groups. In addition, significant differences were revealed in the BMC of the LS, the BMD, T-scores ( P < 0.001), Z-scores ( P = 0.001), and in the BMC of the FN ( P < 0.001), the BMD (P = 0.001), T-scores, and Z-scores ( P < 0.001), respectively. In addition, the HIRT group's bone indices were considerably greater than those of the LIRT group ( P < 0.00). Nonetheless, LIRT was significantly greater than that of the control group ( P > 0.00). Conclusion: According to the current findings, HIRT seems to be the most effective training program compared with LIRT for bone indicators improvement in the femur neck and the lumbar spine among postmenopausal women with osteopenia